Product accumulation systems are routinely used in conjunction with conveyors for the storage and accumulation of product which is fed from an upstream source onto conveyors. In the normal operation of this type system, product is placed on a conveyor at the upstream location, for instance at one operational station, and then transported to a downstream location by conveyor where the next step in the manufacture or distribution of the product is to be accomplished.
It is not uncommon that, during this process, there may be a disruption at a downstream location caused by a malfunction of machinery, some constraining problem, or other circumstance which prevents downstream machine from accepting products. Continued operation of production upstream may result in the build-up of line back pressure which could cause a further problem in permitting the unrestricted movement of product. However, if such a disruption is one which can be addressed relatively quickly, upstream product which normally would be transported to the malfunctioning location, can be received and temporarily stored by an accumulator which is integral to the system.
By employing such an accumulator, the upstream machinery can continue to operate by moving product to the accumulator. Since product movement can continue, there is no build-up of line pressure. Such a system also saves the substantial time and expense which would result in having to shutdown and then restart the entire system, if no accumulator was otherwise available.
As product is being received and retained by the accumulator, the downstream problem can be addressed. When that part of the system resumes full operation, the products stored in the accumulator are released to the downstream destination, with little downtime to the system. Products can also be received and stored at the accumulator in case there is an upstream disruption. In this case, accumulated products could be retained and sent downstream in order to keep the system operational while the upstream problem is being remedied.
Co-pending U.S. application Ser. No. 09/984,682, relates to a product conveying and accumulation system with multiple conveyors, including product supply and discharge conveyors and an accumulator conveyor. The accumulator conveyor in this system efficiently and smoothly receives product for accumulation, should there be a disruption in the system, and for effectively delivering product to conveyors for downstream destinations, after the disruption is addressed. However, an important consideration not included in this application, and inadequately addressed by prior conveyor/accumulator systems, concerns the need to ensure that product which has been placed on accumulator systems does not languish on the accumulator component of the system, while later delivered product is being transported downstream. This xe2x80x9cfirst in-first outxe2x80x9d concept takes on greater significance when the product being transported is perishable in nature. Such products will spoil and be lost if allowed to remain on accumulators, in favor of product which is newly received from upstream sources.
It is thus the object of the present invention to overcome the limitations and disadvantages of prior product conveying and accumulation systems.
It is an object of the present invention to provide a product conveying and accumulation system and method which allows products received and accumulated during the production process to be delivered to downstream destinations efficiently and effectively.
It is a further object of the present invention to provide a product conveying and accumulation system and method which generally ensures that first product into the system is the first product out.
It is thus an object of the present invention to provide a product conveying and accumulation system and method in which products transported to the accumulator component are delivered to downstream destinations substantially in the order they enter the system.
It is still another object of the present invention to provide a product conveying and accumulation system and method substantially ensures first in-first out product transfer while allowing upstream supply to the system from a variety of entry points.
These and other objects are accomplished by the present invention which consists of a product conveying and accumulation system for use with products of various sizes, shapes and stability characteristics. The system comprises multiple moving conveyors, including a first conveyor which transports product from an upstream location to the inner path of an accumulator conveyor. The accumulator conveyor, traveling at a substantially similar speed or a designated variable speed as the first conveyor or conveyors, is aligned in the same plane as, is adjacent to, and may mate with the first conveyor at a predetermined location at the inner path of the accumulator conveyor for contiguous movement in the same direction as the first conveyor at this predetermined location. As product from upstream is delivered to the inner path of the accumulator conveyor, it eventually travels to the outer path and then accumulates inwardly, such that the earlier delivered product remains substantially at the outer path, where a product guide generally directs product on the outermost paths to the downstream destination. In this manner, the first products which are delivered to the accumulator conveyor are generally the first products transported downstream.
Novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention, itself, however, both as to its design, construction and use, together with the additional features and advantages thereof, are best understood upon review of the following detailed description with reference to the accompanying drawings.